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31.
Background/aims  Surgical resection of choledochal cysts (CC) has become standard treatment. However, surgery is not universally recommended in early infancy and/or asymptomatic patients. In order to investigate the optimal timing of CC excision, we analyzed clinicopathological data and surgical results from different age groups. Material and methods  This retrospective review included 107 patients (77 females, 30 males) who underwent CC resection at the National Taiwan University Hospital between January 1988 and December 2005. Patient demographic, clinical, and surgical data were collected and analyzed. Results  The patients were divided into three groups according to age at the time of surgery: <1 year old (group I, n = 26), 1−16 years old (group II, n = 48), and >16 years old (group III, n = 33). About two thirds of the patients in group I had jaundice, while abdominal pain related to inflammation was the commonest symptom in groups II and III. Group I suffered significantly fewer surgical complications and less severe liver fibrosis than groups II or III. Conclusion  CC surgery in infancy and in asymptomatic patients is safe and may prevent the complications of this condition. The results support a recommendation for early excision.  相似文献   
32.
Decompressive hemicraniectomy as an appropriate treatment for malignant middle cerebral artery (MCA) infarction is still a controversial issue. This study aimed to determine the survival rate and functional outcome, and factors associated with these, in patients with malignant MCA infarction. From January 2000 to December 2003, 60 patients with malignant MCA infarction were treated in our hospital. All patients in the study underwent a large ipsilateral craniectomy and duroplasty for decompression. The infarction territory was evaluated by either diffusion weighted magnetic resonance imaging or computed tomography. Clinical neurological presentation was evaluated using the Glasgow Coma Scale. Functional outcome was evaluated using the Barthel index (BI) and the Glasgow Outcome Scale (GOS) at follow-up 12 months later. Thirty-day mortality was 20% (12 patients) and 12-month mortality was 26.6%. The factors associated with higher mortality were age>or=60 years, involvement of more than one vascular territory, presence of signs indicating clinical herniation before surgery, and treatment more than 24 hours after ictus. The mean GOS score was 3.3+/-1.7. The mean Barthel index was 65.1+/-40.1. Twenty-nine (65.9%) patients had a favourable outcome (BI>or=60). The factors associated with favourable outcome were age<60 years and treatment within 24 hours of ictus, before clinical signs of herniation were noted. Decompressive hemicraniectomy should be performed in patients younger than 60 years within 24 hours of ictus before clinical signs of herniation develop. Age, timing of surgery and clinical signs of herniation are prognostic factors for mortality and functional outcome.  相似文献   
33.
Sympathetic skin response (SSR) and R–R interval variation (RRIV) were studied in 36 chronic, nondiabetic uremics to compare with their nerve conduction studies (NCS) and clinical dysautonomia. Abnormal SSR was noted in 5 (13.9%) patients, abnormal RRIV in 14 (38.9%), and abnormal NCS in 26 (72.2%). The patients were classified into three groups: group (GP) 1: “normal,” n = 21 (58.3%), normal RRIV and SSR; GP 2: “isolated parasympathetic dysfunction,” n = 10 (27.8%), abnormal RRIV and normal SSR; and GP 3: “sympathetic sudomotor dysfunction,” n = 5 (13.9%), abnormal SSR. A significant difference in age was found among the three groups (GP 3 > GP 2 > GP 1; P < 0.0001, ANOVA). After controlling the age factor, we still noted a tendency toward increasing NCS disturbances (distal latency and nerve conduction velocity of peroneal nerve; P < 0.05, multiple regression analysis) and frequencies of clinical autonomic symptoms (postural dizziness and impotence; P < 0.05, Mantel–Hanszel test) from GP 1 to GP 3. Patients with abnormal SSR (GP 3) displayed significantly higher frequencies of postural dizziness and impotence, indicating the relationship between an absence of SSR and clinical dysautonomia. © 1994 John Wiley & Sons, Inc.  相似文献   
34.
OBJECTIVE: To determine the frequency of mutations in the regulatory domain of the gap junction protein connexin 43 in patients with visceroatrial heterotaxy. DESIGN: Mutation screening of the terminal 200 base pairs of connexin43 gene coding sequence in a series of patients from tertiary care centres. PATIENTS: 48 patients with visceroatrial heterotaxy attending UK Regional Paediatric Cardiology Centres. RESULTS: No changes from the published connexin43 consensus sequence were found in any of the 48 patients studied. CONCLUSIONS: Germline mutations of the phosphorylation sites in teh regulatory domain of the connexin43 gene are rare in patients with visceroatrial heterotaxy.  相似文献   
35.
The medialis pedis flap (MPF) has been used for the reconstruction of soft-tissue defects in the hand since 1990. From January 1997 through January 2000, 19 patients (15 male, 4 female) with hand injuries underwent microsurgical MDF reconstruction at Chang Gung Memorial Hospital. There were finger injuries in 16 patients and palm defects in 3 patients. The mean patient age was 32.6 years (age range, 16-58 years). Flap size ranged from 4.5 x 2 cm to 7 x 6 cm (mean, 6 x 2.8 cm). Only one flap had partial loss. The donor site was closed primarily in 9 patients, and was closed using a split-thickness skin graft in 9 patients and a full-thickness skin graft in 1 patient. At a mean follow-up of 13 months, the protective sensation was 16 mm using the static two-point discrimination test and was 10 mm using the moving two-point discrimination test. Based on this retrospective study the authors conclude that (1) the MPF has the advantages of thin and glabrous skin, (2) the size of pedicle is compatible with the recipient vessel in the hand, (3) there is low donor site morbidity, and (4) achieving protective sensation is possible.  相似文献   
36.
To evaluate the catabolic effects of dexamethasone therapy on protein metabolism, amino acid concentrations and urinary 3-methylhistidine (3MH) were measured in 28 premature infants who were included in a double-blind controlled study using early dexamethasone therapy in the prevention of bronchopulmonary dysplasia. Fifteen infants received dexamethasone (0.5mg/kg/day i.v.) and 13 infants received normal saline as control. Heparinized venous blood samples for amino acid analysis were obtained before the study and again at day 5 after starting the study. Urinary 3MH was measured on days 1, 3, 5, 7, 14, 21, and 28 of treatment. A substantial increase in amino acid concentrations was observed in infants receiving dexamethasone. Alanine, glutamine, citrulline, ornithine and cystine concentrations increased twofold or more. The 3MH:creatinine ratio was increased in the treated group. These metabolic effects were most likely due to an increase in protein catabolism.  相似文献   
37.
Surveillance methods that measure St. Louis encephalitis (SLE) virus activity in nature may provide forewarning of its epidemic occurrence in humans. An antigen capture enzyme immunoassay was developed to detect SLE virus in infected mosquitoes. The assay detected purified SLE viral antigen at a concentration of 62 pg/0.1 ml when antigen was incubated overnight; 250 pg/0.1 ml was detected in a single-day assay (antigen incubated for 3 h). The assay detected 67.9 and 70.8% of laboratory-prepared pools of infected mosquitoes after 3 h and overnight incubation, respectively. The sensitivity of the procedure was 90.5% in identifying pools with infectious titers greater than dex 3.0. The specificity of the assay was controlled by retesting positive pools preincubated with SLE virus and normal antibodies, which led to a diminution of signal in the pools containing viral antigen. The procedure was suitably specific in discriminating between SLE and related flaviviruses, detecting only high infectious doses of heterologous antigens.  相似文献   
38.
Identification of novel steroid-response elements.   总被引:3,自引:0,他引:3  
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39.
Recent studies have suggested that the "pressor effect" of acellular Hb is a consequence of perturbation of the macro-and microcirculatory system in multiple ways, and that PEGylation is an effective approach for controlling the same. In an attempt to confirm this concept, a new and simple thiolation mediated, maleimide chemistry-based conservative PEGylation protocol has been developed to conjugate multiple copies of PEG-chains to Hb. This approach combines the high reactivity of maleimides towards thiols with the propensity of iminothiolane to derivatize the epsilon-amino groups of proteins into reactive thiol groups, with conservation of their positive charge. One of the PEGylated products, namely (SP-PEG5K)6-HbA, that carries on an average six copies of PEG5000 chains per Hb, is non-hypertensive in hamster top load and in rat 50% exchange transfusion models. This hexa-PEGylated-Hb has (i) a hydrodynamic volume corresponding to that of an oligomerized Hb of 256kDa, (ii) a molecular radius of approximately 6.8 nm, (iii) high oxygen affinity, (iv) lowered Bohr effect, and (v) increased viscosity and colloidal osmotic pressure. These properties of (SP-PEG5K)6-HbA are consistent with the emerging new paradigms for the design of Hb based oxygen carriers and confirm the concept that the "pressor effect" of Hb is a multifactorial event. The thiolation mediated maleimide chemistry-based PEGylation protocol described here for the generation of (SP-PEG5K)6-Hb is simple, highly efficient, and is carried out under oxy conditions. The results demonstrate that a non-hypertensive PEG-Hb can be generated by conjugation of a lower number of PEG chains than previously reported.  相似文献   
40.
Hyaluronic acid (HyA) has the intrinsic ability to promote cell proliferation and reduce scar formation. However, the clinical use of HyA has so far been limited because of its water solubility and nonadhesive characteristics. Increasing interest in HyA as a clinically useful biomaterial has prompted our study of altering HyA's physical properties to render it a potential component of nerve grafts. In this study, strands of HyA were cross-linked by glutaraldehyde (Glut), coated with polylysine, and then inoculated with Schwann cells (SCs). Results in vivo and in vitro demonstrated that cross-linked HyA strands were water insoluble and thus less biodegradable. Poly-D-lysine-resurfaced strands showed significant SC attachment of 350-400 cells/mm(2), compared to uncoated controls (0-10 cells/mm(2), p < 0.01). Fibroblast control groups showed an attachment of 40-100 cells/mm(2) on coated strands. Immunostaining for proliferating cells showed SCs as and fibroblasts as +. Cells neither adhered to nor proliferated on the modified HyA strands that were not resurfaced. The results suggest that polylysine promotes SC attachment and proliferation to glutaraldehyde-cross-linked HyA strands, the product being a three-dimensional composite with low solubility that may have potential application in nerve grafts.  相似文献   
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